body {
    margin: 0;
    padding: 0;
    width: 100vw;
    height: 100vh;
    overflow: hidden;
    transition: all 0.4s ease-out;
}

// Transition
.entering,
.entered {
    opacity: 1;
}

.exiting,
.exited {
    opacity: 0;
}

// CSSTransition
.alert-enter {
    opacity: 0;
    transform: scale(1.1);
}

.alert-enter-active {
    opacity: 1;
    transform: scale(1);
    transition: opacity 300ms, transform 300ms;
}

.alert-exit {
    opacity: 1;
    transform: scale(1);
}

.alert-exit-active {
    opacity: 0;
    transform: scale(0.9);
    transition: opacity 300ms, transform 300ms;
}